Improvement in the manufacture of white lead



, with Oil.

i NITED STATES l PATENT Finch.

S. R. BRADLEY, OF NEW YORK, N. Y.

IMPROVEMENT IN THE MANUFACTURE OF WHITE LEAD.

Specilicationyforming part of Letters Patent No. 95,075, dated September 2, 1869.

To all whom it may concern.:

Beit known that I, S. R. BRADLEY, of the city, county, and State oi' New York, have made al certain new and useful Improvement o in the Process of Manufacturing the Pigment after having been produced is carried through a succession of washings in water, and that when that part of the process is completed it is in admixture with water and in a thick liq uid state, termed in the trade, pulp,77 and that in that state it ispumped up into large shallow vats and there exposed day and night to a considerable heat to expel all the water by evaporation preparatory to grinding it On transferring it afterit has been dried from the drying-pans tothe places where it is mixed With oil the finer particles scatter in the air, exposing the operatives to its deleterious effects. i

The object of my invention is to avoid the expense of drying the pulp preparatory to grinding in oil, and atlthe same timeto avoid, the deleterious effects due to the moving of the pigment in` the state of adry powder; and

to this end my said invention consists in mixingthe pulp directly with oil and subjecting the mixture to the action of beaters or stirers, by means of which acomplete admixtnre of the oil and pigment is effected and the water completely separated, so that it can be drawn off.

The manner in which I have successfully worked my said improved process is as follows, viz: I take the pulp-that is corbonate of lead and water-after the last washing,and while it is in the condition in which it is usually transferredto the drying-pans, and run it into a vessel, A, ttedwith a suitable It is well known that the carbonate of leadl cover, B, and add the required quantity of oil, and there subject it to the beating action of beaters G on arms projecting from a vertical shaft, D, driven by any suitable motor, until it is found by inspection that the pigment and oil have been thoroughly united and the water separated. The rotation of the beaters is then stopped and the whole permitted torest until the separated water appears of' a bluish tint, at which time this water is drawn oiiC through a discharge-pipe, E, at the side into any suitable vessel, and if any ofthe mixed pigment and oil shall pass into the receiving-vessel it can be there collected by permitting it to settle and drawing od the water; and' it the water should be found to contain any `material portion of the pigment which has not been taken up by the oil it can be subjected a second time with oil to the action of the beaters and treated as beforel stated, or it can be subjected to the action ot' the beaters with a fresh charge of pulp and oil. The pigment so mixed with oil can be packed for use just as it comes from the treatment above described, or it can be run through the mill; and,althongh I have above described the kindv of apparatus in which I havesuccessfully worked my said improved process, I do not wish to be understood as confining myself to the use of suchapparatus, as other suitable meansV may be substituted for the working of S. R. BRADLEY.

Witnesses:

WM. H. BIsHor, WM. F. MGNAMARA. 

